The chronology of the martian volcanoesThe volcanoes of Mars have been divided into three groups based on morphology: basaltic shields, domes and composite cones, and highland patera. A fourth group can be added to include the volcano-tectonic depressions. Using crater counts and the absolute chronology of Soderblom, an attempt is made to estimate the history of the volcanoes. Early in the martian history, about 2.5 b.y. ago, all three styles of volcanoes were active at various locations on the surface. At approximately 1.7-1.8 b.y. ago a transition occurred in the style and loci of volcanic construction. Volcanoes of younger age appear to be only of the basaltic shield group and are restricted to the Tharsis region. This same transition was noted by a change in the style of the basaltic shield group. Older shields were small low features, while the younger shields are significantly broader and taller.
Document ID
19800039554
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Plescia, J. B. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena; Southern California, University Los Angeles, Calif., United States)
Saunders, R. S. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena Calif., United States)